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to pinpoint the best possible operating
condition with less human effort.
The new test station can be paired with
a single-site handler and thermal control
solution to create a remotely accessible test
platform, which has proven its worth during
the recent COVID pandemic. The approach
also lends itself well to “copy-exact”
implementations where PSV test floors
support highly-parallel device validation
efforts. This approach supports concurrent
testing with fewer “bench” engineers,
thereby cutting TTM and reducing the
validation costs.
Figure 6: Replacement of a multi-instrument bench top with a streamlined integrated system.
Production test allow both the structural and functional It’s quite prophetic how the writer of Star
It is becoming vividly clear that nearly test selection process to proceed more Trek: the Next Generation had a robot named
all test content needs to move to the wafer intelligently. Several questions hint at how Data that provided such a key function on
test step if we are to have any chance to proceed: the Enterprise D. Clearly, the role of data in
of achieving KGD. It has also become the future will continue to expand and grow.
abundantly clear that we have entered a • Why not pull in vision inspection data Data himself gave voice to the challenge in
space where we have too many tests and and use it to decide which corner of the front of us: “It is the struggle itself which is
not enough time to run all of them. It’s not die to test first? most important. We must strive to be more
unusual for manufacturers today to have • Why not use the in-line parametric test than we are. It does not matter that we will
to cull about 10% to 50% of their available data to anticipate power extremes and never meet our ultimate goal. The effort
pattern sets at wafer probe because of appropriately adjust limits up front? yields its own rewards [5].”
vector-memory and/or test time limitations. • Why not use the results for the first few
The question moving forward is how to wafers to direct which tests should be References
choose which patterns to run at each test executed subsequently? 1. Charts derived from an extended
insertion point. Optimal results depend analysis of test-data-volume estimate
on which test content is best executed at Summary in Logic Test section of Test
the first wafer-probe test experience, the As we move into 21 century test, things Technology Working Group’s update
st
subsequent KGD test probe test step, the will become much more focused and to the Heterogenous Integration
post-assembly test step, and the final SLT dynamic. There is little doubt that data Roadmap, https://ieee.webex.com/
step. Today, this is an art left to the senior will be king. There is no doubt that test ieee/lsr.php?RCID=6f8af4b048a444
test strategists. Moving forward, this art over HSIO interfaces will become critical 1e9501ea473be02921
will benefit from AI-driven tools and broad- to test time reductions. And perhaps most 2. ibid
based data sharing. important, the role of big data in determining 3. D. Armstrong, “Shift left,” MEPTEC
While structural and functional test the value and limitations of each device Known-Good Die Workshop, Sept.
content both have their place, functional being tested will be solidified. 25, 2022, https://www.youtube.com/
test methods can more quickly confirm the The introduction of the EX Test Station watch?v=YObxvk5sqSQ&t=241s
proper functioning of large blocks of logic (Figure 6) provides a new tool to simplify, or 4. D. Armstrong, “Heterogeneous
as compared to structural test methods, possibly eliminate, yesteryear’s bench setup, integration prompts test content to ‘shift
which check one gate at a time. The author replacing multiple instruments and tangles left,’” Chip Scale Review, Feb. 2021,
expects an increased usage of functionally- of wire (Figure 6a) with a streamlined p. 7. https://chipscalereview.com/wp-
capable test modules, such as Link Scale™, integrated system (Figure 6b). The new test content/uploads/flipbook/1/book.html
in production as a new tool to provide more station provides for a clean and consistent 5. “69 Best Data Quotes from Star Trek
test coverage in less test time. workspace that also happens to be identical TNG and the Star Trek Movies,”
The big opportunity for growth in this to the setup used in production testing on Soda and Telepaths, April 26, 2021.
space, however, is with the addition of the V93000 ATE. A consistent interface https://sodaandtelepaths.com/69-
data-driven test selection techniques that achieves consistent results. data-quotes-from-star-trek-tng/

Biography
Dave Armstrong is Principal Test Strategist at Advantest America, Inc., San Jose, CA. In addition to his
work with many of Advantest’s customers, he has also served as the Chairman of the Test Technology Working
Group for the Heterogeneous Integration Roadmap. He has degrees in Electrical, Computer, and Environmental
Engineering from the U. of Michigan. Email Dave.Armstrong@Advantest.com

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